Lost fifth gear. Broken gearbox?

[K-Man]

I hooked fifth and heard a strange noise yesterday, was like it wouldn't engage. Permanent neutral in fifth after that but the first four works fine. What's the probable issue you think? What do I need to order for when I split my cases? Bent fork? Worn selector drum or a cleared out gear like others have had?

[blownbillybob]

Bent fork or bent fork shaft?????

[K-Man]

The other four worked fine the rest of the day so figuring the noise (like brrrrrrrrrrrrrrrrr) it made, it might well have cleared some teeth off the gear. I overhauled the engine last winter with new bearings and all and all gears looked fine then...

But I suppose it's not much point speculating. I'll just have to split the cases and look I guess

Do I change one, two or all gears while I'm at it? They seem a bit expensive on ebay...

[black]

Maybe the dawgs broke off and is slipping or fork and it don’t want to pull the gear over so the dawgs can hook up, but you wont know untill the cases get split.

[kkvslayer]

Happened to me on my 86,was the 3rd and 5th gear engagement dogs,can't remember which shaft,I ended up swapping out the whole tranny,same deal 1st to 4th still worked fine

[K-Man]

I split the cases just now and the only worn thing I can find are the dogs pictured below. Shift forks and drum are ok as well. No broken teeth or dogs.
Wierd. Ideas why fifth wouldn't engage?

[black]

Put the gearbox in the right side cover with the shift drum and forks in place with all the parts under the clutch cover installed that is needed to select gears. Leave the left case of then turn the gearbox and select the gears from the clutch side, but put drag on the gearbox (counter shaft) and see what hooks up and not. The gear on the right side of the one with the worn dawgs is the main shafts fifth gear and it must be the worn edges that are the problem. Buy a tranny of EBay. It sucks working on it when you could be riding it.

[K-Man]

Good tip and words of wisdom. Thanks Mr Black!

[scooter5002]

If youre only changing the minimum of pafts, change the gear to the right.of fhe one you have circled. The one the dogs engage. If ones bad, the other one is usually part of the problem. Check the shift fork as well. Its likely bent, which would be why the gears stopped engaging properly. Even if it looks okay, change it anyway. Been through this enough times myself.
Be sure and flush out those cases and bearings thoroughly. You dont want shrapnel from your gears rattling taking out a bearing a month after you get it back together.

[gregrobo]

mine did the same replace the gears 1st to 4th but no 5th or it throws out with a clunck common in 500s

[kkvslayer]

I split the cases just now and the only worn thing I can find are the dogs pictured below. Shift forks and drum are ok as well. No broken teeth or dogs.
Wierd. Ideas why fifth wouldn't engage?

That is exactly what mine looked like

[K-Man]

That gear and corresponding fork will cost me 260 $ here in Sweden and Honda-parts direct don't seem to ship internationally (they charge 120 $). Any tips of someone who ships overseas?

[kkvslayer]

That gear and corresponding fork will cost me 260 $ here in Sweden and Honda-parts direct don't seem to ship internationally (they charge 120 $). Any tips of someone who ships overseas?

I would get that gear with the worn engagement dogs and the corresponding gear it mates with because having those rounded off edges bashing on the corresponding gear no doubt wore it down too,shift fork as well,You can pick up good used complete trannys on ebay for a couple hundred bucks,swap the output shaft bearing to the correct one for whatever year tranny you get and its a direct swap,if you want to only swap the broken parts then get both because it will be a major pain if you put it all back together and your still runnin a four speed,perhaps someone could accept the order here in North America for you then ship it to you